Isolation of Phytase Producing Bacteria and Optimization of Phytase Production Parameters

Background: Cereals, legumes, and oilseed crops are very important crops as nutrition for human and animals. Phytate (myo inositol hexa kis phosphate) is the main storage form of phosphorus in these crops. These crops are major source of nutrients for humans and animals including fish, poultry and pig. Phytic acid is the nutritional constituent of animal diet but it is not digested by monogastric animals because they do not contain phytase enzyme in their intestines to break the phytic acid and due to this, phytic acid acts as an anti-nutritional chelating agent for various metal ions like Ca, Mg, Fe, Zn, and etc., so that reduced the nutritive quality of food. Objectives: Phytase is an important enzyme in the food/feed industry; therefore, isolation of phytase producing bacteria and optimization of phytase production on different parameters were performed in this study. Materials and Methods: The present study was conducted in Biotechnology laboratory, Motilal Nehru National Institute of Technology, Allahabad, Uttar Pradesh, India. To isolate phytase producing bacteria from different soil samples like cattle shed, pulse crop field, poultry farms, and etc. 0.1 gr of the soil samples were streaked on phytase screening medium. The qualitative screening of the isolates was performed on phytase screening medium plate with 1.5% agar, and phytase activity was determined by using shaking flask method. The best phytase producer was optimized using different parameters of phytase production. Results: We isolated 32 phytase producing bacteria on phytase screening media. Upon screening of these strains, one of the best strain (DR6) which showed a 39 mm clear zone on phytase specific medium (PSM) was identified as Bacillus subtilis. So this strain was selected for further enzymatic assay and optimization. This strain showed 378U/mL enzymatic activity upon enzymatic assay, the result of optimization of this best strain was performed at different parameters, and this strain showed best results at pH 5.5, Temp 50 degrees C with Glucose + Sucrose as Carbon source and Yeast extract as Nitrogen source. Conclusions: The present study suggests that the enzyme obtained from strain B. subtilis can be used as feed supplement in animal diet also for reduction of phosphorus pollution problem in areas of livestock production.